Electric heater



1. 1.. w. SERRELL Jan. 15 1924' ELECTRIC HEATER s Sheets-Sh 1 Filed 16 fig. 1.

3 Sheets-Sheet 2 Jan. 15, 1924- r L W. SERRELL ELECTRIC HEATER Filed Oct. 16 1920 5 M a 1, m w 4 m J 7 f 1. w 2 2, 2 h S 3 n w 2d u m4 3 7 w 2 m IH (2W w ,2 ml? E C m 9 T. MI m m W 2 m m LI L E 1 Jan. 15, 1924.

aimummmllmmum 7 [mural i. Mfr/"1! $3M 4M whom Laid I county, and

10 boiling water tion, I employ very small portion of 4 to radiate its heat directly into the air.

amount of the ly on the bottom of the vessel placed above deflector warms that surrounds Patented 1 5, 1924.

LEHUEL 'W. SEBBELL, OF NEW YORK, N. Y.,

1,480,787 OFFICE.

Assmuon 'ro snnnm ELECTRIC urn- ANCE CORPORATION, A CORPORATION OF DELAWARE.

ELECTRIC manna.

Application fled October 1a, 1920. Serial No. 411,372.

To all whom it ma concern:

Be it known that LEMUEL W. Samara, a citizen of the United States, residing at the borough of Manhattan, in the city,

State of New York, have invented an Improvement in Electric Heaters, of which the following is a specification.

- My invention relates to electric heaters for cooking purposes, and particularly for quickly. In electric heaters heretofore made of this character, the heating elements have been laid in porcelain or similar material; embedded between iron lates or in cast iron, and the heat generated the assage of electric current throu 11 such reslstance wires is radiated uniform y in all directions, that radiatin downwardly being absorbed by the porce ain or other material causing a waste of energy, as only 20 a limited amount'iof the heat is free to function directly upon the vessel containing the water to be boiled.

The object of my present inventionis to rovide a device in which to impinge directly upon the bottom of the pot or vessel containing the liquid, whereby a maximum efliciency is obtained Without wastage of heat. In carrying out my invena concave reflector parabolically shaped, preferably terior surface, into which I insert radiant heating coils openly supported on a skeleton frame of insulating material and so con- 8 structed as to practically fill the interior of the reflector. These openly supported radiant coils are so arranged that only a the coil touches the balance of the coil being free The skeleton support does away with absorption and conduction losses and permits the heat to rise naturally, and by deflection from the polished surface of the reflector. A greater heat is thus free to act directsupport, the

the heater, the heat however, that is reflected from the concave deflector, heats the same and this heat being conducted through the the air on the under side of the reflector to a high temperature, and to save this wastage I provide, first, an apron the reflector and which slopes downwardl and outwardly so that I should liquid boi over it will run away from and not into the reflector. vide a shell which is fastened SldB of the apron, but

the heat generate by v :6 the electric current is concentrated and caused polished on its in-' I also proto the under spaced therefrom so as to leave an air space between it and the apron, with an opening to the atmosphere around the outer edge of the apron, an also provide a series of air vents around the periphery of the concave reflector containing the heating element, all so arranged that the air in the confined space between the reflcctor and apron and the shell which is heated, may escape through these vents and add its heat energy to the column of heat rising from the heating element. In doing so, it causes cold air to be drawn in at the outer edge of the apron, which travels to the center, down the inner surface of the lower shell, Where it rises and replaces the escaping heated airon concave reflector. A circulation of air is thus established that absorbs a large amount of the heat conducted through the reflector that would otherwise be wasted, which heat is not only used effectively on the bottom of the vessel containing the liquid, but the circulation of the air cools the concave reflector, stops any injury to the reflecting surface which might occur by the intense heat from the radiant heating coil, and gives a maximum efleciency to the entire heating element. By this new and novel construction I produce a torch like heat column similar to that produced by a gas range burner that will boil water in practically the same time as a as ran e'burner, whichno other form of e ectric liot plate as yet devised will do. I

The details of construction and operation are hereinafter particularly described.

In the accompanying drawings:

Figure 1 is an elevation of my improved electric heater complete. 1

Fig. 2 is a central vertical section of the same.

Fig. 3 is a top view of the same, the grate being removed.

Fig. 4 is a top view of the reflector.

Fig.

Fig. 6 is an elevation of the heating element removed.

Fig. 7 isa bottom plan view of the same.

Fig. Sis a side view of one of the arms of the supporting frame for the heating coil, and

Fig. 9 is a top view of the same.

the under side of the 5 is an inverted plan of the same. I

I, so

till

i with spaced openings,

parts throughout the several views.

l0, indicates a preferably polished on ing a circular apron ll lfrom and surrounding its periphery. ,'.lh1s apron may be integral with the rellector, but it prefer to provide the reflector wlth an annular flange l2 around its eriphery to whiclrthe apron is secured. lnt e preferred form,- the apron has a central circular opening of slightly larger diameter than the upper part of the reflector, so that when the reilector is placed into 12 will rest upon the Similar reference characters denote like its interior, and havextcnding outwardly top of the apron. 'lUniformly spaced openings are made in the apron adjacent its inner edge, and similar and aligned openings are made in the dange 12 of the reflector, thus forming a seriesot air vents 13 around the periphery of the retlector. The apron may be secured to the redoctor in any suitable manner, but I prefor to e oy eyelets 14: which may be inin two or more of the aligned openings forming the air vents, as shown.

The apron is preferably slo ed slightly downwardly away from the re rector for the purpose of carrying. any liquid that might oil over, and it may he stepped concentrically as shown, for the purpose of giving it greater stillness. The outer edge or the apron extends horizontally and is provided with spaced openings for thepurpo-se hereinafter set forth.

l5 denotes an outer shell provided with a horizontal annular flange 16' ot corresponding diameter to the outer edge of the apron ll; this flange 16 is also provided corrmponding and in alignment with the openings in the outer edge ot the apron. The apron ll and the outer shell ac secured together by bolts 17 which pass through outer horizontal edge oil apron and flange it or the shell, there losing spacing sleeves l8 surrounding said holts between the respective flanges, which serve to separate the apron and shell a predetermined distance, leaving cold air inlets l9 therebetween,

The bottom of the reflector 10 is preferably flattened at its center and provided with three spaced openings therein. 20 denotes a disk oi insulating material secured to the under side of the reflector 10 at its center by sleeve or eyelets 21 passing through the openings in the bottom of the reflector and through similar and aligned openings in the dish. The lower ends of these eyelets 21 also pass through openings in one end or contact strips 22, the ends of the eyelets being upset within the reflector and upon the contact strips 22. The tree ends of these contact strips are upwardly turned over the outer edge of the dish 20, and each strip is metallic concave reflector such opening its tlangc 1'1 the openings in the i l, ,m

' rovided with a threaded hole to receiye the inding screws 23 for the conductor wires 24, there being aligned holes through the disk 20 into which the ends of the screws 23 may pass. Insulating bushings 25 are employed to prevent contact between the reflector and the eyelets '21.

26 indicates a heating coil which is arranged within the redector 10 upon a skeleton support comprising at arms 27 of insulating material, each arm being convergingly beveled vertically at one end whereby these ends of the respective arms 't together ata common centerwith the arms extending therefrom in spaced vertical relation to each other Uri-the upper and lower edges of each arm adjacent its beveled end there is a notch 28; 29 and 30 are two metal disks, each provided with a central opening and overturned on er edge, which are placed at the top and bottom of the arms 27 at their meetin point when assembled, the overturned e ges of the dislr into the notches 28 on the arms. screw 31 is passed through the ooenings in these disks nut 32 screwed upon the lower projecting end of the screw, thus securely holding the arms 27 together, there being suflicient space between the assembled ends or the arms to permit of the passage of said screw..-

Thetop edges or the arms 2? are in the same horizontal plane, their free ends being curved to conform to the interior'ot the reflector, and both the top and curved edges of these arms are provided with spaced incesses or open slots 33.

Vertically disposed terminal contacts fit, 35, 36ers secured to three at the arms 2? (one contact to each arm) by bolts or screws 37, the lower ends of such contacts being split longitudinallyand extending below the arms 27 a predetermined distance.

The heating coil 26 is uniformly wound around the skeleton support, being inserted into the recesses or slots 33in the respective 26 is connect ed and a ltlli to the contact 34: by a binding screw 38 and the other end of the coil is nected to one of the 35 or 36. Holes in the arms '27 through which end or ends of the heating coil 26 may he passed to facilitate connection with the terminal contacts.

lln placing the heating element within the c reflector, theprojecting lower split ends of the terminal contacts 3t, 35, 36 are pushed through the sleeves or eyelets 2i connecting the insulating disk 20 with the under side of the reflector, thus making electrical connection with the lead wires 24; these terminal contacts not only facilitate the proper positioning of the heating element within the reflector, but'a'lso serve to hold it in lined relation thereto.

similarly conother terminal contacts 39 are preferably provided A grate 41, is placed over the heating element, being seated upon the apron 11, the

outer edge of the flange 12, of the reflector ing such opening, but I prefer to provide legs 40, as .shown, so that the device may be stood upon a table or upon any other convenient support.

By the employment of the skeleton frame for the heating. coil, only a comparatively small portion of the coil contacts with the supporting arms of the frame, which leaves the major portion free to radiate the heat directly into the air, thus greatly lessening absorption and conduction losses, the heat rising naturally, and by deflection from the polished surface of the concave reflector,

while the use of the apron and lower shell,

with the cold air inlets and heated air outlets provided thereby, gives additional heat energy to the column of heat rising from the heatlng coil. The circulation of air produced by this arrangement at the same time cooling the concave reflector, thereby preventing any injury to the reflecting surface from the intense heat from the radiant heating coil, giving a maximum efficiency to the entire heating element.

I claim as my invention:

1.. An electric heater comprising a concave reflector, an openly supported electric heating element therein consisting of a resistance coil and an insulating supporttherefor comprising a plurality of divergent arms provided with notched edges into which said coil is inserted and uniformly wound about said support and terminal contacts, forming means'by which said heating element may be placed in or removed from said reflector.

2. An electric heater comprising a concave reflector, an openly supported heating element uniformly distributed within the same and an apron surrounding said reflector.

3. An electric heater comprising a con- 7 cave reflector, an openly supported heating coil uniformly distributed within the same, anapron'surrounding said reflector, aclower shell and means for attaching the same thereto and in spaced relation therefrom.

4. An electric heater comprising a concave reflector, an openly supported heating coil uniformly distributed within the same,

-an apron extending outwardly from said reflector and surrounding the same, a series of air vents surrounding the peri hery of said reflector and a lower shell held in spaced relation therefrom.

e, flange 16 of the shell- 15 resting upon the top of the oven surroundcave reflector,

5. An electric heater comprising a con cave reflector, an insulating support therein consisting of a plurality of divergent arms connected together at one end and curved on their free ends to conform to the shape of the reflector, each arm being provided with spaced notches on its edges and a resistance coil inserted into said notches and uniformly wound about said support.

6. An electric heater comprising a conan openly supported heating coil uniformly: distributed within and substantially filling the same, an apron extending outwardly from said reflector and surrounding the same; a lower shell held in spaced relation from said apron so as to leave an air space between, with an opening to the atmosphere, and a series of air vents surrounding the periphery of the reflector through which the side of the reflector may heated air on the under escape while cold air is drawn from the atmosphere to replace the same.

7. An electric heater comprising a concave reflector, a heating coil, an insulating support for the same consisting of a plurality of divergent arms connected together at one end, each arm being provided with spaced notches on its edges to support said coil, an apron extending outwardly from said reflector and surrounding the same; a lower shell fastened to, but in spaced relation from said apron so as to leave an air space between, with an opening to the atmosphere, and a series of air vents surrounding the periphery of the reflector through which the heated air on the under side of the reflector may escape, while cold air is drawn in from the atmosphere to replace the same.

8. An electric heater comprising a concave reflector provided with an outwardly i turned annular flange having spaced apertures therein an apron connected to said flange, a lower shell, means for supporting the same below the apron in such manner as to leave an air space therebetween, an openly supported heating coil within the reflector, and a skeleton insulating support for said coil.

9. An electric heater, comprising a concave reflector, a heating element located sub- LEMU'EL W. SERRELL. 

